Let DF=1, DG=x. AF is perpendicular to DE. From the right triangle EAD we get EG*GD=AG^2, so AG=sqrt((1-x)x). From the triangle FGD we get GF=sqrt(1-x^2). But GF=1-AG, so we get an equation sqrt(1-x^2)=1-sqrt((1-x)x). Solving for x we get x=4/5. So DG=4/5, EG=3/5 and ED=5/5. Piotr Chrzastowski-Wachtel, University of Warsaw, Poland.